Got fuel? Do you use a fuel cutoff for winter storage? I imagine it has a fuel pump. If you pull the fuel line from tank to pump, does fuel flow freely?
Have you tried starting fluid? If you have any 2 stroke fuel, you can spray a little in the carb and see if it fires. If not, need to check for spark. The light bulb testers don't really tell you much.
In my experience, this is usually fuel related. Either crud in tank, or carb.
